Hello everybody, Master Yeed here. I have been playing league of legends since season 2, and I have been playing Master Yi from the start. I somewhat mained him, but then I had to quit league of legends for various reasons. When I came back, AP Yi was not a thing. But now, he is back. Do you want to pentakill in less than 10 seconds? Do you want to snowball harder than Yasuo/Teemo/Fizz? If yes, Master Yi is for you. For starters i would recommend AD Yi just because it is a bit easier.

On Master Yi, his every auto attack does magic damage. Meaning, the more AP you have the more damage you do. Guinsoo's rageblade + Hextech gunblade is a crazy combo for Master Yi. You also heal from 30% of all damage sources, which includes magic damage. So, you heal from your W, and you heal from making damage. This build will not work for other lanes than jungle. This is because of the Skirmisher's sabre.

The runes above are masteries for AP Yi. Why do we need magic penetration? With this AP build you will apply on hit magic damage + attack damage so penetration runes are pretty good.

AD RUNES:
3x Quints of attack speed
9x Marks of attack speed
9x Seals of armor
9x Seals of magic resist

The Masteries which I used above are masteries for AP Yi. If you are going AD Yi, you will have some crit which means bloodlust would be very good. Assassin is also a very good mastery compared to Runic Affinity.

This should be rock hard. You should focus like this: R > Q > E > W
Q > W > E > Q > Q > R > Q > E > Q > E > R > E > W > E > W > R > W

Always start with a hunter's machete. You can take health pots instead of the refillable potion if you want to go ham and cheese early game. You have to build into Skirmisher's Sabre Devourer as fast as possible. Then, buy these items. Speed is very important for Master Yi just because the more he hits the less Cool down is on his Q/Alpha Strike

AD MASTER YI: Skirmisher's Sabre Devourer, Berserker Greaves, Blade of the Ruined King, Statikk Shiv, Infinite Edge, And Blood Thirstier.

AP MASTER YI: Skirmisher's Sabre Devourer, Sorcerer's Boots, Guinsoo's Rageblade, Hextech Gunblade, Nashor's Tooth, and Rabadon's Deathcap.

Double Strike
After landing 3 basic attacks, Master Yi's next basic attack within 4 seconds strikes twice, dealing 50% AD physical damage which applies on-hit effects and can Critical strike icon critically strike.
Additionally, Master Yi's dance speed increases with his movement speed.

Alpha Strike
RANGE: 600 COST: 70 / 80 / 90 / 100 / 110 MANA COOLDOWN: 18 / 17 / 16 / 15 / 14
ACTIVE Master Yi blinks to the target enemy and up to 3 consecutive nearest enemies, becoming untargetable in the process, deals physical damage to each of them, increased against minions and monsters, and reappears next to his primary target.
PHYSICAL DAMAGE: 25 / 60 / 95 / 130 / 165 (+ 100% AD)
ENHANCED DAMAGE: 100 / 160 / 220 / 280 / 340 (+ 100% AD)
Alpha Strike can Critical strike, dealing 60% AD physical damage to all enemies, modified by bonus critical damage. Basic attacks reduce Alpha Strike's cooldown by 1 second.

Meditate
COST: 50 MANA COOLDOWN: 35
ACTIVE: Master Yi channels for up to 4 seconds, healing himself each second for an amount increased by 1% for every 1% of his missing health.
「 MINIMUM HEALING PER SECOND: 30 / 50 / 70 / 90 / 110 (+ 15% AP) 」
「 MINIMUM TOTAL HEALING: 120 / 200 / 280 / 360 / 440 (+ 60% AP) 」
While channeling, Master Yi reduces incoming damage, halved against turrets.
「 DAMAGE REDUCTION: 50 / 55 / 60 / 65 / 70% 」
Meditate resets Master Yi's autoattack timer.


Wuju Style
COOLDOWN: 18 / 17 / 16 / 15 / 14
PASSIVE: Master Yi gains 10% AD as bonus attack damage while Wuju Style is not on cooldown.
ACTIVE: Master Yi's basic attacks deal bonus true damage for 5 seconds.
BONUS TRUE DAMAGE: 10 / 15 / 20 / 25 / 30 (+ 10 / 12.5 / 15 / 17.5 / 20% AD)

Highlander
COST: 100 MANA COOLDOWN: 75
PASSIVE: Champion takedowns reduce the current cooldown of Master Yi's basic abilities by 70%.
ACTIVE: For 10 seconds, Master Yi gains bonus attack speed, multiplies his movement speed and becomes immune to all Slow icon slows. While active, champion takedowns extend the duration of Highlander by 4 seconds.
MULTIPLIED MOVEMENT SPEED: 25 / 35 / 45%
BONUS ATTACK SPEED: 30 / 55 / 80%

Sometimes, timing on Master Yi is super important. As you have read, Meditate reduces all incoming damage. This means you can avoid turret shots/ults/1 shots. Alpha Strike does the same thing, but better. You can completely dodge everything without getting even 1 single damage. If you got a kill under tower with your Q, Meditate until Alpha strike is off cooldown and Alpha strike on enemy minions to avoid turret shot because tower aggro will go off.

CONS
-Hard to comeback if behind
-Attack speed reliant (a bit)
-Farm reliant

PROS
+You can dodge any kinds of damage
+Pentakill in less than 10 seconds
+Fun to play
+Huge AP heals
+Huge damage

Start with a hunter's machete, health potions/refillable potions, and a ward. Go for gromp and ask your team to help you. Smite gromp. Go for blue and then for red. Then go for Crimson Raptor. Now, you can go where you'd like. Get skirmisher's sabre as fast as possible and get 30 stacks.

GANKING IS IMPORTANT - GANKING IS IMPORTANT - GANKING IS IMPORTANT

Thank you everyone for reading this guide. I hope this helped and you enjoyed it. Please leave a comment and up vote this guide because it helps me.
Play Video Cowsep is golden.

Checkout my Jax guide! http://www.mobafire.com/league-of-legends/build/6-1-hybrid-jax-top-and-jungle-purple-god-444999